Question

Tìm x, biết:

(x - 2).(x + 2/3) > 0

Ai giải nhanh đúng mk tick cho

Answer 1

\(\left(x-2\right).\left(x+\dfrac{2}{3}\right)>0\)

=>\(x-2\) và \(x+\dfrac{2}{3}\) cùng dấu

Ta có 2 TH :

+)TH1:\(\left\{{}\begin{matrix}x-2>0&x+\dfrac{2}{3}>0&\end{matrix}\right.\Rightarrow\left\{{}\begin{matrix}x>2\\x>\dfrac{-2}{3}\end{matrix}\right.\Rightarrow}x>2}\)

+)TH2:\(\left\{{}\begin{matrix}x-2< 0\\x+\dfrac{2}{3}< 0\end{matrix}\right.\Rightarrow\left\{{}\begin{matrix}x< 2\\x< \dfrac{-2}{3}\end{matrix}\right.\Rightarrow x=\dfrac{-2}{3}\)

Vậy \(x>2\) hoặc \(x< \dfrac{-2}{3}\)